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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>交集选择器</title>
    <style>
        /* 是div，且class是c1 */
        div.c1 {
            color: #fdf000;
            font-size: 16px;
        }
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</head>
<body>
    <h1>交集选择器</h1>
    <ul>
        <li>多个选择器必须都满足，才能使用上样式</li>
        <li>使用次选择器在于更加精确地查询元素</li>
    </ul>
    <div class="c1">1</div>
    <div class="c1">2</div>
    <div class="c1">3</div>
    <div class="c1">4</div>
    <div class="c1">5</div>
    <div>6</div>
    <p class="c1">1</p>
    <p class="c1">2</p>
    <p class="c1">3</p>
    <p class="c1">4</p>
    <p class="c1">5</p>
    <p>6</p>
</body>
</html>